Telephone-receiver apparatus



May 4 1926.

J. FLEISCHMAN TELEPHONE RECEIVER APPARATUS Filed June 1922 i To all whomit 71mg.conce rwh' Patented May 4', 1926.

I JOSEPHILEISCHMAQT, orivnw YORK, N. Y.

' rnrnr onn-nnonrvna APPARATUS.

Application-filed June 24,

Be it known that I, J'osEPH FLmsoHMAma citizenof the U'nited States, andresident f 1 a pluralityof persons withoutincurring the "listening in bya .multiplicity of persons distortions commonly associated with the useof amplifying horns Another object is tOK-PI'OVldB a radio re} ceivingset which shallre'nderpossible the without. the need for more than onetelephone diaphragmg I -Another object is to provide a distributingreceiver unit susceptible of use with asingle ordinary watch-typetelephone receiver for ,cating. a preferred application of the re- 1P-faithful and efiicient delivery to a plurality oflisteners. p I

Otherobjectswill be in part obvious and in part pointed out.hereinafter.

In the accompanying drawings in which is shown one or more of variouspossible embodiments of the several features of this invention,

Fig. 1' is a transverse sectional view of a preferred" form ofdistributing receiver,

Fig. 2 is a plan view thereof,

Fig. 3 is'adetail sectional view on an enlarged scale taken along theline 3 3 of Fig.1,

Fig. 4 is a transverse sectional view on' a smaller scale of amodification, I I

Fig. 5 is a' transverse fragmentary view I of a further modification,and i Fig. 6 is a diagrammatic planview indi ceiver.

Referring now to the drawings, I have shownin Figs. 1, 2 and 3 adistrlbutlng re-f ceiver comprising a base block 1 of gen'erah lycylindrical form having preferably a felt support 2. The telephonereceiver proper is mounted upon the upper end of the block; Thisreceiver comprises the usual watchtype casing 3 enclosing the usualelectromagnets 4. and has the usual threads '5 at will be obvious.

1922; Serial"No.= 570,745.

the exterior thereof for tl'le earPlate. The? r Y upper 'e'n' d of thesupport block is tap ped I as: at 6 land the" casing 3 is threaded there1 into, instead of into 'anearplate'.

telephone diaphragm 7 1preferablyrests' upon a peripheral ledge 8forme'd': on

anannular hardflrubber plate 9' fitting snugly into an annular.depression 10' I in the support block below the tapped pertion 6,: thereceiver: casing when threaded home preferably clamping the diaphragm-7f'l 7 against thep'eriph'eral ledge 8 and clamping the disk 9'against thesupport blockl, a

felt washer 11 being preferably interposed to- 'render the connectionsound tight-V The lower surface of'the disk 9 ispreferably dished as at12"aboutthe central aperture 13 substantiallyin the manner of the ordinary receiver earplate" and may, if desired,- be formed:from'theordinary'earplate of a 'telephonereceiver by removing the-periphthemanner Whicl'ri eral portion thereof in ltwillbe: seen that the mu aircame.

lt'below the diaphragm" and disk 9 constitutes. a sound chamber.fromawhich the vibrations originating in the di aphragm, are tobe passedonto the 'various listeners; a preferred form the support'block' has"small cylindrical. depression or well- 15 below the: sound chamber andcommunicates with' preferably four radial -ducts-:16{.throu 'li..- thedistributing. block 'in' which fit' nipp es.

17, anyone or moreof which may bGfCOIl carry. the usual ear pieces ;19forinsertion,

one into each auditory orifice. l odistrib ute' the sonorous energyequally and symmetrically to. the various outlets, :I prefer ablybinaurals,the outer endsof which may to fit a spider 20rinto thecylindrical de-..

with rubber gaskets 24 to form a'ir tight range of the apparatusarelistening.

The sound and llstrlbutlng ch ambersjlare ofsuch small volume as to beresonant to a pitch above: the range of audibility, asd is tinguished'from a. sound chamber of materially larger dimensions" that willresonateto *closuresfor the outere'nds of'the-nipples- 1.7' for those tubes notin use, when lessfthanthe maximum number of persons within the V someone definite pitch and may correspond ingly distort the sound.

In Fig. 4 is shown an alternative, form of the invention in which thebase block has a cylindrical distributing chamber'25, nipples 26 inducts 27 extending radially through the wall 28 for connection of thesound tubes 18. The diameter, of this chamber is preferably not morethan 2.5 inches to avoid resonating to a high pitch within .the range ofaudibility.

In Fig. is shown another alternative form in which the distributingchamber 29 is of inverted generally conical form,.ducts 3O radiatingfrom near the tip 31 thereof for connection of the nipples 32. Thevibra-g tions from the diaphragm, it will be seen generate correspondingvibrations in the chamber 29 which pass toward the .tip 31 thereof, butare relievedthrough the radiating ducts and nipples 32 and pass on tothe binaurals.

Except as heretofore described, the embodiments shown in Figs. 4 and 5are preferably identical with that of Figs. 1 and 3.

In use, the multiple distributor may be placed upon a table, thetelephone wires 33 1 and 34: being connected to the familiar telephoneterminals of the radio set and each listener will take a pair ofbinaurals, caps 23 being used to close any nipples out of use.

In a preferred embodiment, the multiple receiver may be mounted upon orwithin a radio receving set of generally conventional externalappearance. Fig. 6 shows a familiar form of such set including a box 35having a panel 36 behind which is mounted a detector tube 37 visiblethrough aperture 38 and adjustableby knob 38, operating knobs, one ofwhich is shown at 39, serving for effecting the usual tuningadjustments, the terminal bin-dingposts for the ground and for theantenna being shown at 40 and ll. In my preferred form of set,

the usual telephone terminals would be omitted, and in lieu thereof,there would be sockets as at 4.2 for attachment of binaurals 18, thesesockets being connected by conduits 43 to the multiple radio receiverRof any of the constructions previously described, mounted in anyconvenient manner preferably within the box and to the rear of thepanel. Thus, the telephone would be concealed and the binaurals merelywould be handled and used by the listeners. Of course, caps such as at44 would be furnished to close' any sockets not in use when the numberof listeners is less than the maximum permitted by the range of thedevice.

Thus, it will be seen that I have provided a multiple telephone receiverof general application, but more particularly use ful for radioreceiving sets. The device utilizes but a single telephone diaphragmandthus dispenses'with the need for a telephone or a pair of telephonesforeach listener. It will be noted that the diaphragm vibrations aretransmitted to the multiplicity of listeners without the distortionscommonly accompanying the use of sound It W111 thus be seen that thereis herein described apparatus in which the several features of thisinvention are embodied, and

which apparatus in its action attains the" various objects of theinvention and is well suited to meet the requirements of practical use.w

As many changes could be made in the above construction, and .manyapparently widely different embodiments of this invention could be madewithout departing from the scope thereof, it is intended that all mattercontained in the above description or shown in the accompanyingdrawings'shall be interpreted asillustrative and-not in a limitingsense.

Having thus described my invention, what I claim as new and desire tosecure by Letters-Patent of the United States is 1. In a distributingtelephone receiver, in combination, a base block, an annular diskfitting into a corresponding depression in said block, and having :aperipheral ledge, a

diaphragm resting upon said ledge, an electromagnet casing threaded intosaid base block and engaging theperiphery of said diaphragm to clampthe, same in position,

and ductsthrough said base block in com-.

municationwith said depression to distribute the sonorousvibrationsgenerated by the diaphragm.

2. In a distributing telephone receiver, in

combination, a base block, aninsulating an-- nulus resting in the upperend of said block and dished at the surface thereof facing said blockand having a peripheral ledge at the 1 other side thereof, a diaphragmrestingupon riphery at the lower surface thereof and having a ledgeabout its outer periphery at the upper surface thereof, the upper end ofsaid base block being interiorly threaded to accommodate the threadedperiphery of the electromagnet casing ofan ordinary tele phone, wherebyupon threading said casing into the upper end of said base block, thediaphragm will be clamped into effective po sition to set the air insaid chamber into vibration and to distribute the sound there fromuniformly through said ducts.

4. In a. distributing telephone receiver, in combination, a base blockhaving a cylindrical chamber therein of dimensions to resonate to apitch beyond the range of audibility, radial outlet ducts in said blockcommunicating with saidchamber, and a telephone receiver threaded intosaid block and having a diaphragm across said chamber.

5. In a distributing telephone receiver, in combination, a base blockhaving a cylindrical chamber, in theupper end thereof, radial outletducts communicating through thelateral wall thereof, a telephonereceiver having an earplate annulus resting upon a flange near the upperend; of said base block, a

diaphragm resting upon said annulus, and an electromagnet containingcasing threaded into the upper end of said block to'clamp the peripheryof said'diaphragm in posi-. tion against said annulus. i

' 6. In a distributing telephone receiver, in combination, a base blockhaving a small central distributing chamber generally conical inform,radial outlets extending through said block and communicating with saidchamber, an ear plate fitting into a corresponding cylindricaldepression in said block and above sald chamber and having a peripheralledge, a diaphragm resting upon said ledge and a telephone receivercasing combination, a base block having a cylindriev cal axial welltherein, ducts radiating from said well, apartition spider constructionfitting into said well and 'frictionally held against adjoining wallportions between said ducts, and atelephone receiverunit havingdiaphragm connected to communicate its vibrations to said well.

Signed at New'York 1n the county of New York and State of New York, this.ZQndday so of June, 1922.

JO FLEISCHMAN.

